Multi-layer catheter tubes with odor barrier

ABSTRACT

A multi-layer odor barrier catheter tube for a fecal drainage catheter. The layers of the catheter tube include one or more thermoplastic elastomer layers and one or more odor barrier layers. For example, the catheter tube may comprise an inner thermoplastic elastomer (TPE) layer, an intermediate odor barrier film layer, and an outer TPE layer. Alternately, the multi-layer catheter tube includes an inner TPE layer sandwiched between outer layers of odor barrier film material.

REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of U.S. patent application Ser. No.12/238,584, filed Sep. 26, 2008, which claims the benefit of the filingdate of U.S. Provisional Application No. 60/976,214, filed Sep. 28,2007. The entirety of U.S. patent application Ser. No. 12/238,584 isincorporated herein by reference.

FIELD OF THE DISCLOSURE

This disclosure is generally directed to medical tubing and, morespecifically, to multi-layered tubing having odor barrier propertiessuitable for use as catheter tubing for fecal drainage systems, and acombination odor barrier tube and odor barrier collection bag.

BACKGROUND

Catheter tubes for fecal drainage systems are designed to facilitateflow of fecal matter, with the fecal matter typically draining into acollection bag. A catheter tube can include a lubricious coating on aninterior of the tube to facilitate movement of fecal matter. Byproviding a multi-layer catheter tube with at least one odor barrierlayer, the catheter tube can reduce or eliminate exposure of thepatient, caregivers, and other persons in the vicinity of the patient tounpleasant odors. Also, because it is desirable for rectal catheters tobe retained in the rectal cavity for extended durations, it has beenfound beneficial to provide rectal catheters with a transsphinctericregion that is collapsible in response to contraction of the patient'sanal sphincter muscles, as described in U.S. Pat. Nos. 7,147,627 and7,722,583. Silicone is a preferred material for the transsphinctericregion.

In providing a catheter tube extending between the transsphinctericregion and a collection bag, not only is it desirable to prevent odortransmission, but it is also desirable to provide resistance to kinkingof the catheter tube, because kinking can obstruct the flow of fecalmatter therethrough. Fecal drainage systems are frequently employed incombination with enema, lavage, or other irrigation techniques to loosenstool in the rectum of a patient. As a result, water or other liquid islikely to travel through the catheter tube with fecal matter. While suchliquid reduces the need to provide a lubricious surface on the interiorof the catheter tube, it is desirable for the exterior of the cathetertube to be lubricious, as this facilitates milking the catheter tube tomove waste material along the length of the catheter tube.

SUMMARY OF THE DISCLOSURE

In preferred embodiments of the present disclosure, the catheter tubingfor a fecal drainage system is made of at least two layers of differentmaterials. The layers are preferably co-extruded, or one layer may beextruded and one or more layers may be subsequently applied by extrusionover the first layer. Alternatively, the layers may be formed as agenerally flat laminate sheet that is rolled into a tubular shape, thensealed along a seam, for example using sealing technology such as heatsealing, RF sealing, adhesive sealing, or ultrasonic welding. In orderto increase the catheter tube's durability, a semi-rigid mesh or scrimmaterial may be included as at least one of the layers of the flatlaminate sheet that is rolled into a cylinder.

Another desirable feature of a catheter tube for a fecal drainage systemis minimal wall thickness. The multi-layer odor barrier catheter tube ofthe present disclosure can be manufactured with a total wall thicknessin the range of about 10 mil to about 60 mil, and preferably with atotal wall thickness of 25 mil. The total wall thickness of 25 mil ispreferable for all embodiments of the catheter tube described herein,regardless of the arrangement of catheter tube layers and the totalnumber of layers.

The odor barrier layer or layers may be a resin, preferably a polyamide,and most preferably nylon 669 or nylon 669 blended with reactive rubber.In one embodiment, an odor barrier layer is sandwiched between twolayers of thermoplastic elastomer (TPE). In another embodiment, aplurality of odor barrier layers may be alternately sandwiched between aplurality of layers of TPE. In yet another embodiment, the odor barrierlayer is an intermediate layer of a plurality of layers of the cathetertube.

To prevent kinking of the catheter tube, which may adversely impact thecatheter tube's function, a low compression set thermoplastic elastomeris preferably used for each of catheter tube's TPE layers. The inner TPElayer, which is thicker than the one or more outer TPE layers and whichmakes up the bulk of the overall thickness of the catheter tube,preferably has a thickness in a range of 12 mil to 24 mil, and mostpreferably has a thickness of 18 mil. The outer TPE layer preferably hasa thickness in the range of 5 mil to 8 mil, and most preferably has athickness of 6 mil. The outer TPE layer may be formulated so as toexhibit high lubricity, i.e. a low coefficient of friction. Highlubricity of the outer TPE layer facilitates relative movement of alatex- or non-latex-gloved hand along the exterior of the catheter tubewhen milking contents of the catheter tube toward a collection bag influid communication with the interior of the catheter tube. Whilelubricity of the inner TPE layer may also be desirable to promote orfacilitate flow of fecal matter through the catheter tube, it is foundthat there is typically sufficient liquid content with the waste matterdraining through the catheter tube such that the inner TPE layer neednot exhibit as high a lubricity as the outer TPE layer.

The odor barrier layer of the catheter tube of this embodimentpreferably has a thickness of 3 mil or less, most preferably 1 mil, andthe thickness of the odor barrier is preferably less than 30% of thetotal tube wall thickness.

In an embodiment of the present disclosure, one or more layers of TPEmay be sandwiched between two or more layers of odor barrier materialsuch as nylon PA 669 or nylon PA 669 blended with a reactive rubber. Inanother embodiment, a TPE layer is an intermediate layer of a pluralityof layers of the catheter tube.

In this embodiment, the inner TPE layer, which also makes up the bulk ofthe overall thickness of the catheter tube, preferably has a thicknessin a range of 10 mil to 60 mil, and most preferably has a thickness of24 mil. Each of the outer odor barrier layers preferably has a thicknessin the range of 0.25 mil to 1.5 mil, and most preferably has a thicknessof 0.5 mil, such that the overall thickness of the catheter tube is,most preferably, 25 mil. While lubricity of the inner nylon layer may bedesirable to promote or facilitate flow of fecal matter through thecatheter tube, as before, there may be sufficient liquid content withthe waste matter draining through the catheter tube of this embodimentsuch that the inner nylon layer need not exhibit as high a lubricity asthe outer nylon layer.

A beneficial aspect of the catheter tube of embodiments of thisdisclosure is the ability of the catheter tube to block unpleasantodors. However, if the collection bag into which the catheter tubedrains lacks odor barrier properties, unpleasant odors can escape thecollection bag, thereby negating the odor barrier benefits achieved bythe odor barrier catheter tube of this disclosure. It is thereforepreferable that the odor barrier tube to drain into a collection bagthat itself has odor barrier walls.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a perspective view of a first embodiment of a multi-layer odorbarrier catheter tube of the present disclosure;

FIG. 2 is an axial cross-sectional view, taken along lines 2-2 of FIG.1;

FIG. 3 is an axial cross-sectional view, similar to FIG. 2, of a secondembodiment of a multi-layer odor barrier catheter tube of the presentdisclosure, wherein tie layers are provided between the first and secondlayers, and between the second and third layers;

FIG. 4 is a perspective view of a heat-laminated film employed in amethod of manufacture of a multi-layer odor barrier catheter tube of thepresent disclosure;

FIG. 5 is a perspective view of the heat-laminated film of FIG. 4,rolled into a cylindrical shape and sealed along a seam;

FIG. 6 is a perspective view of a heat-laminated film similar to that ofFIG. 4, and including a flexible scrim layer;

FIG. 7 is a perspective view of the heat-laminated film of FIG. 6,rolled into a cylindrical shape and sealed along a seam;

FIG. 8 is a front view of a combination of a multi-layer odor barriercatheter tube of the present disclosure in combination with a drainablecollection bag having odor barrier walls;

FIG. 9 is a front perspective view of a combination of a multi-layerodor barrier catheter tube of the present disclosure in combination witha closed, single-use collection bag having odor barrier walls;

FIG. 10 is a perspective view of a third embodiment of a multi-layerodor barrier catheter tube of the present disclosure, including anoutermost ethylene methyl acrylate (EMA) film surrounding an outerthermoplastic elastomer layer, the EMA film serving as a siliconebonding substrate;

FIG. 11 is a cross-sectional view, taken along lines 11-11 of FIG. 10;

FIG. 12 is a perspective view of another embodiment of a multi-layerodor barrier catheter tube of the present disclosure, wherein theinterior and exterior layers comprise an odor barrier material; and

FIG. 13 is a cross-sectional view, taken along lines 13-13 of FIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1-2, in a first embodiment of a multi-layer odorbarrier catheter tube 10 of the present disclosure, the catheter tube 10is connectable at a first end to a patient-proximal internal section,and/or a trans-anal section of a rectal catheter (not shown). Thecatheter tube 10 is also connectable at a second end to a wastecollection bag or to a disposal receptacle (e.g., a bedpan or toilet(not shown)). At least one layer of the multi-layer catheter tube 10 isconstructed of a material resistant to transmission of fecal and flatusgasses. A suitable material is nylon, and preferably low-modulus nylonsuch as nylon PA 669. EMS-Grivory's GRILON® BM 13 SBG is a suitablelow-modulus nylon, with its modulus of approximately 43 ksi compared totypical nylon PA6 with a modulus of about 100 ksi. Another suitablematerial is nylon PA669 blended with reactive rubber to reduce themodulus and set of the blend. For example, nylon PA669 could be blendedwith Kraton® FG1924, LOTADER® 4720, or DuPont Fusabond® 493. A suitableblend would be, for example, 75% EMS-Grivory GRILON® BM 13 SBGcompounded with 25% LOTADER® 4720. In addition, one or more lubricantsmay be added to the blend. These lubricants may include, for example, anamide wax (e.g., erucamide, oleamide, stearyl erucamide), an ester wax(e.g., esters of montanic acids), or silicon oil preferably used at0.05% to 0.5% loading to generate a low surface coefficient of friction.

A first layer or outer layer 12 of the catheter tube 10 defines theexternal surface 14 of the catheter tube 10. The outer layer 12 ispreferably comprised of one or more materials that possess a relativelylow coefficient of friction, most preferably less than 0.5, so as toreduce drag of the catheter tube 10 against a patient's skin and againstany items surrounding the patient, such as a hospital gown, bed sheets,or a chair. The low coefficient of friction of the external surface 14of the catheter tube 10 also facilitates “milking” the fecal matter downthe length of the catheter tube 10.

The material or materials defining the outer layer 12 of the cathetertube 10 include a thermoplastic elastomer (TPE), preferably having athickness in the range of 4 mil to 8 mil, and most preferably athickness of 6 mil. TPE exhibits adequate lubricity, particularly TPEhaving a Shore A hardness of approximately 60. The external surface 14of the outer layer 12 is preferably a surface that will receive inkssuch as permanent or semi-permanent markers and retain such markingsthereon without smudging or wiping off. This will facilitate receivinginstructions, patient data, collection bag change data, dates of indwellor intended removal of the catheter tube, and other such indicia.

An intermediate layer 16 of the catheter tube 10 of an embodiment of thepresent disclosure is an odor barrier film layer, preferably apolyamide, and most preferably nylon 669.

second layer or inner layer 18 of the multi-layer catheter tube 10 of anembodiment of the present disclosure preferably comprises TPE having athickness in a range of 12 mil to 24 mil. The inner layer 18 mostpreferably has a thickness of 18 mil. The inner layer 18 is preferablythe thickest layer of the catheter tube 10 and is formulated for lowcompression-set, with high elasticity, as this is found to render thecatheter tube 10 more resistant to developing kinks, such as when foldedin packaging material.

Depending on the compatibility of the materials of adjacent layers ofthe multi-layered catheter tube 10, as shown in FIG. 3, a tie layer 22,such as DuPont Bynel®, may be employed between adjacent layers toimprove adhesion of the adjacent layers to one another. However, in apreferred embodiment of the present disclosure, the materials ofadjacent layers of the multi-layer catheter tube are compatible and donot require a tie layer be employed between adjacent layers to improveadhesion of the adjacent layers to one another.

The multi-layer catheter tube 10 of the first embodiment of the presentdisclosure may be manufactured by co-extrusion. In order to maximizetube softness and flexibility, it is desirable that a catheter tube 10of some embodiments of the present disclosure include a single, thinodor barrier layer, preferably 1 mil. In embodiments of the cathetertube 10 with more than one odor barrier layer, the odor barrier layerspreferably have a thickness of 0.25 mil to 1.5 mil.

Turning to FIGS. 4-5, as an alternative to co-extrusion, the layers ofthe catheter tube 10 may be formed into a flat or substantially flatheat-laminated film 24 and then rolled into a cylinder. For example, inone embodiment of the present disclosure as illustrated in FIGS. 4-5,two parallel edges 26, 28 are rolled toward one another, brought intoregister with one another, and sealed to one another, such as by heatsealing, RF sealing, adhesive sealing, or ultrasonic welding, to form acylinder, with the first layer 12 of the film 24 defining an externalsurface 14 of the cylinder and the inner layer 18 defining an internalsurface 20 of the cylinder. A leading end 30 and a trailing end 32 ofthe heat-laminated film 24 are left open, forming first and second ends34, 36 of the catheter tube 10. Optionally, tie layers (represented bybroken lines in FIG. 4) may be provided to enhance bonding between theinner layer 18 and intermediate layer 16, and/or between theintermediate layer 16 and the outer layer 12. The outer, inner, andintermediate layers 12, 18, 16, respectively, of the catheter tube 10are preferably clear or translucent. The sealed edge or seam 38 may bevisible and can advantageously provide a medical caregiver with avisible indicator of any kinking or twisting of the catheter tube.

The total cumulative wall thickness of the multi-layer catheter tube 10is preferably in the range of about 10 mil to about 40 mil, and morepreferably in a range of about 25 mil to about 35 mil, with thethickness of the odor barrier layer preferably making up less than about30% of the total wall thickness of the catheter tube 10.

Adjustments may be made to process conditions under which the layers ofthe multi-layer catheter tube of the present disclosure are co-extrudedor heat laminated to reduce the coefficient of friction of one or moreof the layers.

In another embodiment, shown in FIGS. 6-7, in order to providereinforcement and avoid kinking or twisting of a catheter tube 40, amesh or flexible scrim layer 42 may be included as an additional layerintermediate the first outer layer 12 and intermediate layer 16 of themulti-layer catheter tube 40. The scrim layer 42, if provided, can serveto provide the catheter tube 40 with shape memory, permitting thecatheter tube 40 to collapse and recover to its cylindrical shapewithout any permanent deformation. Materials other than a scrim layer 42may be used instead of or in addition to the scrim layer 42 to enhancestructural integrity of the catheter tube 40, such as polymericmaterials.

The material(s) forming the internal and/or external surfaces of themulti-layer catheter tube of the present disclosure preferablyfacilitate attachment and assembly of the catheter tube to peripheralcomponents of fecal drainage and management systems, such as the BowelManagement System available from Hollister Incorporated of Libertyville,Ill. As such systems are intended for long-duration use, on the order ofabout twenty-nine days, it is advantageous to employ materials that willeasily form a reliable bond, by adhesive and/or heat, between thecatheter tube 10 and the peripheral components, such as internal orexternal silicone balloons, catheter connections (e.g., a collection bagor a catheter tube extension), plastic or metal ports (e.g., ports forproviding endoscope access or for sampling fecal matter directly fromthe catheter tube) for the entire duration of use of the catheter tube10.

As noted above, the advantages achieved by the odor barrier propertiesof the catheter tubes of the present disclosure would be negated, orsignificantly diminished, if fecal or flatus gasses could be transmittedthrough one or more walls of a collection bag 44 (see FIG. 8) to whichthe catheter tube 10 is connected. It is therefore desirable to use themulti-layer odor barrier catheter tube 10 in combination with acollection bag 44 having odor barrier walls. For example, each of thewalls of the collection bag may include a barrier layer film such as theone disclosed in U.S. Pat. No. 7,270,860.

Turning to FIG. 8, the odor barrier collection bag may be a drainablecollection bag 44, having a drainage tube 46 with a drainage tubestopper 48 and a cap 50 for capping a catheter tube connection port 52.Alternately, as illustrated in FIG. 9, the odor barrier collection bagmay be a so-called “closed” collection bag 54. A closed collection bag54 is intended for single use, and preferably includes an integral vent56 with a deodorizing filter 58.

Turning to FIGS. 10 and 11, an alternate embodiment of a catheter tubeis illustrated in which the TPE layer or outer layer 12 of the cathetertube 10 has an ethylene methyl acrylate (EMA) film 68 bonded, such as byheat sealing, to at least the portion of the exterior thereof that isreceived in the silicone trans sphincteric region 60. EMA film 68 bondsto silicone more readily than TPE. EMA film also exhibits highlubricity, thereby eliminating the need to formulate the TPE layer orouter layer 12 in a manner that increases that layer's lubricity, oreliminating the need to add a lubricious coating, such as Parylene, tothe exterior of the catheter tube 10.

Turning to FIG. 12, in another embodiment of the present disclosure, anintermediate layer 16 comprising TPE may be sandwiched between an outerlayer 12 and an inner layer 18, both comprising an odor barrier materialsuch as nylon PA 669 or nylon PA 669 blended with a reactive rubber. Abeneficial aspect of this embodiment is that by sandwiching theintermediate layer 16 of TPE between the odor barrier layers 12, 18,difficulties of bonding TPE to silicone device components to which themulti-layer tubing 10 is attached may be avoided due to thecompatibility of the nylon odor barrier material and silicone.

The TPE layer or intermediate 16, which makes up the bulk of the overallthickness of the catheter tube 10 of this embodiment, preferably has athickness in a range of 20 mil to 40 mil, and most preferably has athickness of 24 mil. Each of the odor barrier layers in this embodiment,i.e., the outer and inner layers 12, 18, respectively, preferably has athickness in the range of 0.25 mil to 1.5 mil, and most preferably has athickness of 0.5 mil, such that the overall thickness of the cathetertube is, most preferably, 25 mil. Furthermore, while lubricity of thenylon layer or inner layer 18 may be desirable to promote or facilitateflow of fecal matter through the catheter tube 10, there may besufficient liquid content with the waste matter draining through thecatheter tube 10 of this embodiment such that the inner layer 18 neednot exhibit as high a lubricity as the nylon layer or outer layer 12. Inanother embodiment of the present disclosure, the inner layer may behydrophobic.

In each of the foregoing embodiments of the present disclosure, the TPEmaterial may include or may be substituted by thermoplastic polyurethane(TPU), styrene-butadiene copolymer (SBC), thermoplastic vulcanisate(TPV), ethylene propylene diene monomer (EPDM), or any other suitablecopolymer or blend.

While certain embodiments of multi-layer odor barrier catheter tubes,combinations of multi-layer odor barrier catheter tubes and odor barriercollection bags, and methods of manufacturing multi-layer odor barriercatheter tubes are disclosed herein, the appended claims are notintended to be limited thereto. Variations can be made to the disclosedembodiments that are still within the scope of the appended claims,literally or under the doctrine of equivalents.

We claim:
 1. A catheter tube for a fecal drainage system comprising: afirst layer including a thermoplastic elastomer; a second layerincluding a thermoplastic elastomer; and a film layer intermediate thefirst layer and the second layer, the film layer including an odorbarrier material, wherein the film layer is nylon
 669. 2. The cathetertube of claim 1, wherein the first layer defines an internal surface ofthe catheter tube and is the thickest layer of the catheter tube.
 3. Thecatheter tube of claim 2, wherein the film layer intermediate the firstlayer and the second layer is the thinnest layer of the catheter tube.4. The catheter tube of claim 1, wherein the nylon 669 is blended with areactive rubber.
 5. The catheter tube of claim 4, wherein the nylon 669blended with a reactive rubber further comprises one or more lubricants.6. The catheter tube of claim 1, further comprising a fourth layerbonded about at least a portion of an exterior of the second layer, thefourth layer including an ethylene methyl acrylate (EMA) film.
 7. Acatheter tube for a fecal drainage system comprising: a plurality oflayers, at least one of the plurality of layers including an odorbarrier material, and at least one of the other layers including amaterial selected from the group consisting of thermoplastic elastomer(TPE), ethylene methyl acrylate film (EMA), thermoplastic polyurethane(TPU), styrene-butadiene copolymer (SBC), thermoplastic vulcanisate(TPV), and ethylene propylene diene monomer (EPDM), wherein the odorbarrier material comprises nylon
 669. 8. The catheter tube of claim 7,wherein the nylon 669 is blended with a reactive rubber.
 9. The cathetertube of claim 8, wherein the nylon 669 blended with a reactive rubberfurther comprises one or more lubricants.